Homogeneous Raman gain saturation at high pump and Stokes powers

摘要

A Raman gain spectral profile has been measured in a phosphosilicate fiber at high pump and Stokes (signal) wave powers by a coherent anti-Stokes Raman scattering (CARS) technique. It has been shown that the profile saturates homogeneously. The main saturation mechanism is proved to be the pump depletion; i.e., the Raman gain coefficient g(R) does not depend on the pump and signal wave power of several watts. The possible influence of stimulated Brillouin scattering and four-wave mixing is discussed. In addition, a transient regime of the CARS signal has been experimentally observed and theoretically explained. (c) 2006 Optical Society of America.